My IC-733A has full power out on 440 but only 7 watts out on 2 meters (with the high power setting)Would it be foolish to try adjusting the output trimmers on the VHF board ?I am thinking it probably needs a new output transistor/module. Any adviceon how to diagnose ?

1. Check the supply voltage INSIDE the radio in Tx mode. It should be the same as measured at the power supply.2. Check the current draw of the radio in TX mode. If 8-9A the module is fine. Probably bad solder on the switching diode.3. On the module numbering left to right, 1 is input, 2 should be ~12v, 3 ~13v, 4 is output.

If the current draw is low 3-5A and the module voltages are correct it's probably the module but you need more test equipment to verify.

Pin 2 voltage controls the power out. With the power that low(7W) it should be at 12-13v if the power control circuit is working correctly. Normally Pin 2 will be abt 11v. Time to go to the service manual and start troubleshooting.

If you have a variable voltage bench supply you can lift Pin 2 and connect to it. Start at abt 6v. Key the radio and slowly increase the voltage up to 11-12v. The power out will go up to over 50w if the module is good.

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